diff --git a/package.json b/package.json
index 1c73006..9cb17a3 100644
--- a/package.json
+++ b/package.json
@@ -96,7 +96,7 @@
         "classnames": "^2.0.0",
         "coveralls": "^3.0.6",
         "css-loader": "^1.0.0",
-        "cssnano": "^4.1.4",
+        "cssnano": "^9.0.0",
         "eslint": "^6.1.0",
         "eslint-config-standard": "^13.0.1",
         "eslint-loader": "^2.1.0",